Optical Spectra and Exciton State in Vertically Stacked Self-Assembled Quantum Disks

We study the oscillator strengths of the optical transitions of the vertically stacked self-assembled InAs quantum disks. The oscillator strengths change evidently when the two quantum disks are far apart from each other. A vertically applied electric field affects the oscillator strengths severely, while the oscillator strengths change slowly as the radius of one disk increases. We also studied the excitonic energy of the system, including the Coulomb interaction. The excitonic energy increases with the increasing radius of one disk, but decreases as a vertically applied electric field increases.